The present invention relates to molded gaskets, and especially to high temperature-resistant molded plastic gaskets for use in connection with automotive engines and in other environments where similar severe service conditions are encountered.
A wide variety of gaskets have been suggested in the prior art for automotive and other uses. Some such gaskets have been molded of high temperature plastics and have used sealing beads to enhance their sealing characteristics. For example, in U.S. Pat. No. 4,817,969 a molded, fiber filled plastic gasket has sealing beads which are integrally formed with the gasket body. Sealing beads of the types there illustrated are not necessarily the most effective in some gasketing environments, and especially in those in which the flanges to be sealed have substantial warpage, or where substantial variations in the spacing between the flanges to be sealed may occur because of the positioning of the bolts or studs clamping the flanges to each other or for other reasons.
It would be desirable to provide improved gaskets for sealing joints, such as joints in automotive engines, and in particular to provide molded plastic gaskets having improved, integrally formed beads which function to seal without requiring excessively high clamping loads, which are adapted for use in a wide variety of environments, which are adapted for use with imprecise sealing flanges, and which will accommodate to substantial variations in applied clamping loads.